Significance HIV is a sexually transmitted disease and a vaccine capable of preventing sexual transmission of HIV should elicit mucosal immune responses in the genital tract. Objectives To determine recombinant polioviruses expressing SIV antigens can elicit immune responses. Results Five animals were immunized intranasally (IN) with recombinant polioviruses. All animals made anti-SIV IgA responses in rectal secretions and 4 of 5 had systemic anti-SIV antibodies. Two of 5 animals had detectable anti-SIV IgG and IgA antibodies in vaginal secretions. Future Directions Dr. Andino is improving the recombinant polio vectors to increase stability and expression of the inserted genes. Once these new vectors are available, we will test their immunogenicity in macaques. If robust immunity is observed with these new polio vectors, we will challenge the immunized animals intravaginally with SIV. KEY WORDS vaccine protection, mucosal immunity, SIV vaginal transmission FUNDING NIH Grants AI36178 and RR00169